<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport"
        content="width=device-width, initial-scale=1.0">
    <title>canvas基本画图</title>
    <style>
        canvas {
            position: fixed;
            top: 0;
            left: 0;
            background-color: #222;
            width: 100%;
            height: 100%;
        }
    </style>
</head>

<body>
    <canvas></canvas>
    <script src="./js/index.js"></script>
</body>

</html>